Venezuela has arrested two top executives for Venezuela's largest drugstore chain as part of an investigation into what authorities say are illegal practices contributing to the country's chronic shortages.

The attorney general's office says it detained Farmatodo Executive President Pedro Angarita and Vice-president Agustin Alvarez over the weekend, and formally charged them Wednesday with working to destabilise the country.

Farmatodo said earlier this week that its actions are transparent and that its 167 stores nationwide have been inspected numerous times in recent months by the government.

President Nicol·s Maduro has been blasting owners of major retail chains that he accuses of conspiring with opponents to wage an "economic war" against his socialist government.

Government critics warn that the crackdown on Farmatodo could have dire consequences for the economy.

Meantime, national guardsmen and state price adjusters fanned out across Venezuela to impose a military-style occupation with an unusual goal: Making sure shoppers can buy enough sugar.

The South American country's socialist administration temporarily took over the Dia a Dia supermarket chain as part of a crackdown on the private businesses it blames for worsening shortages and long lines. Maduro, who promised to jail any business owner found to be fomenting economic chaos, says right-wing owners are purposely making shopping a nightmare by hoarding goods and removing checkout stations.

On Monday night, Congress President Diosdado Cabello said officials had arrested Dia a Dia's owner and taken over its 35 stores "for the protection of Venezuelans". By Tuesday morning, armed soldiers were overseeing lines for bags of sugar at a Dia a Dia location near the presidential palace.

Many economists blame price and currency controls for causing the economic distortions plaguing the country at a time when falling oil prices are battering its revenues. Analysts see this week's moves against business owners as an attempt to drive home Maduro's counter-narrative that the right wing is waging an economic war.

"The government is starting to prepare for a social explosion," said Diego Moya-Ocampos, an analyst with the London-based consulting firm, IHS Global Insight. "They're trying to channel all the social discontent against the private sector."

Many Venezuelans agree with Maduro. Even Dia a Dia branch manager Carlos Barrios said it was possible that his bosses were hoarding. He had seen the photos government workers had posted outside his store of pallets of sugar, corn flour and toilet paper apparently sitting at the chain's central warehouse.